You do not need to configure a cluster interconnect for a single-node cluster. However, if you anticipate eventually adding nodes to a single-node cluster configuration, you might want to configure the cluster interconnect for future use.
The cluster interconnects provide the hardware pathways for private-network communication between cluster nodes. Each interconnect consists of a cable that is connected in one of the following ways:
Between two transport adapters
Between a transport adapter and a transport junction
Between two transport junctions
During Sun Cluster configuration, you specify the following information for two cluster interconnects:
Transport adapters – For the transport adapters, such as ports on network interfaces, specify the transport adapter names and transport type. If your configuration is a two-node cluster, you also specify whether your interconnect is direct connected (adapter to adapter) or uses a transport junction. If your two-node cluster is direct connected, you can still specify a transport junction for the interconnect.
If you specify a transport junction, you can more easily add another node to the cluster in the future.
Consider the following guidelines and restrictions:
SBus SCI adapters – The SBus Scalable Coherent Interface (SCI) is not supported as a cluster interconnect. However, the SCI–PCI interface is supported.
Logical network interfaces – Logical network interfaces are reserved for use by Sun Cluster software.
See the scconf_trans_adap_*(1M) family of man pages for information about a specific transport adapter.
Transport junctions – If you use transport junctions, such as a network switch, specify a transport junction name for each interconnect. You can use the default name switchN, where N is a number that is automatically assigned during configuration, or create another name. The exception is the Sun Firelink adapter, which requires the junction name sw-rsmN. The scinstall utility automatically uses this junction name after you specify a Sun Firelink adapter (wrsmN).
Also specify the junction port name or accept the default name. The default port name is the same as the internal node ID number of the node that hosts the adapter end of the cable. However, you cannot use the default port name for certain adapter types, such as SCI-PCI.
Clusters with three or more nodes must use transport junctions. Direct connection between cluster nodes is supported only for two-node clusters.
You can configure additional private-network connections after the cluster is established by using the scsetup(1M) utility.
For more information about the cluster interconnect, see “Cluster Interconnect” in Sun Cluster Overview for Solaris OS and Sun Cluster Concepts Guide for Solaris OS.